Process and device for the application of liquids to moving bands of material



J. J. F. STOCK DEVICE FOR THE APPLICATION OF April 21, 1931. 1,801,374

PROCESS AND LIQUIDS T0 MOVING BANDS OF MATERIAL Filed Jan. 12, 1927Patented Apr. 21, 1931 UNITED STATES JOHANN JACOB FRIEDRICH STOCK, FMUNICH, GERMANY PROCESS AND DEvIoE FOR THE APPLICATION 0F LIQUIDS 'roMOVING BANDS or MATERIAL Application filed January 12, 1927, Serial No.160,726, and in Germany J'anuary-14, 1926.

This invention relates to devices for applying liquids to bands orstrips of material, such as photographic films and the like, for thepurpose of coloring, varnishing, emulsioning, and regenerating the same.The

operation of applying liquids to such material for the stated purposemust be carried out with utmost care, especially in the case of ofcinemato raphic films because a thorough- 1y even appdication is ofparamount importance and if perforated films are to be treated, greatcare must be exercised in order to prevent the liquid from passingthrough the perforations onto the other side of the film.

According to certain prior art practices, rollers are used for theapplication of liquids to the cinematographic films. However, theserollers having plain or smooth circum ferences are not able to effect aneven application of the liquids to the films, so that additional means,such as brushes must be used to distribute the material, While stillother means are employed to prevent the liquid from passing through theperforations on the film. 1

According to other prior art practices the film is passed from a pointabove onto the surface of a liquid so that the surfaceof the film wouldonly just touch the level of the liquid.

However, the method or process proved to be impractical and hasbeen'abandoned. The film would often immerse too deep while at othertimes it would not even touch the liquidlevel. The contact of the filmsurface with the liquid level must be exceedingly slight, and since thetravel of the film past the liquid level depends on many circumstances,it is practically impossible to efiect it with the necessary accuracy.

This invention provides an improvement over the last mentioned processand solves the problem in an efficient manner by making use of thecapillary and cohesive properties of the liquids with the assistance ofcertain mechanical devices.

In one embodiment of the invention a roller which is preferably metallicis employed to. rotate with its lower portion in a reservoir of theliquid to be applied, and is provided with a shallow circumferentialgroove,

or crevice of a width corresponding to the.

width of the band, or tothat portion thereof which is to be treated withthe liquid. The liquid is maintained at a constant level within itsreservoir, and when said roller is rotated therein at a predeterminedspeed, it takes up the liquid upon its circumference, mainly within itscircumstantial groove, and carries the liquid therearound in the shapeof a very fine sheet or film. The band or film to be treated is passedwith its sides over lateral or marginal ridges of the roller, so thatthe central portion of the film bridges the crevice of the latter and isthus caused to be in slight superficial contact with the circulatingthin sheet of liquid within said crevice. Owing to the cohesion of theliquid particles, this sheet or film .of liquid adheres to the band andbreaks away only after the film has left the roller in the divergingangle formed between the film and roller.

The accompanying drawing lllustrates, by way of example, a device forcarrying out the aforesaid process.

Fig. 1 diagrammatically illustrates the arrangement in side elevation.

Fig. 2 is a section of the roller and through the liquid reservoir orcontainer.

Fig. 3 is a diagram illustrating the principle of the invention andshows the film or sheet of liquid free from the roller in an exaggeratedrepresentation.

Fig. 4 is a section on the line IVIV of Fig. 2, on an enlarged scale.

In the drawings a band or film a is represented under treatment in thisinstance of solvents or the like, for the purpose of regenerating it soas to remove scratches and other deficiencies. Said film is assumed tohave been first run through a cleaning device preferably embodying ametal wire brush and a vacuum cleaner. The aforesaid cleaning deviceforms no part of the present invention and therefore is not shown in thedrawing. After the application of the liquid by means of the inventivedevice, as

will presently be described, the film is passed through one or morechambers of the machine for any further treatment that may be required.Such further treat- 5 a constant level by suitable means.

ment and the means for effecting it are likewise immaterial to thepresent invention and are accordingly omitted from the drawings.

Guide rolls I) serve to lead the film in known manner through themachine and over the liquid applying disc or roller 0 having'acircumferential groove or crevice carrying a film or sheet of the liquidin application to one surface of the film band as previously de-'scribed. The resilient tension of the film band which is required toensure a correct travel, and above all, an even application of theliquid, is exerted by a weighted roller d which is freely suspended in adepending loop a formed in the film before its communication with saidrollers 0. Above and below said weighted roller are electric contacts 6and gized and attracting the arm 7: of said switch in known manner. Theelectric connections and the way of the current are evident and theyare, therefore, not specially referred to. Closing the contact 0 takesplace when the tension of the band a becomes excessive, while undueslackncss would cause the roller 03 to descend and close the contact 0by its weight.

The essential feature of this invention is the roller 0 for theapplication of the liquid. Said roller turns in anti-friction bearings(not shown) and is driven at a speed proportional to that of the filmpassing over it. It is therefore preferably driven by contact with themoving film itself. Around its circumference the roller 0 is providedwith a shallow groove or crevice f. Its lower portion extends into atrough or the like 7 in which the liquid which is applied to the film iskept at When said roller 0 rotates at a predetermined speed, smallparticles of the liquid adhere to it within the shallow groove f byreason of the cohesive properties of the liquid, and are flung aroundwith the roller in the shape of a thin sheet or film of liquid. It isobvious that the quicker the roller rotates the more liquid it will takeup within its crevice so that the film always receives the correctamount and it is immaterial whether the arrangement works, withinpractical limits, at high or low speed. The fine film of liquid passesup with the roller until its surface unites with the surface surfacesuntil, at the departure of the film band from the roller, the thin sheetof liquid breaks away. The tension required to main tain the film ineven contact with the roller varies according to the kind and materialof the film or band, and it is for this reason that the regulatabletensioning device re resented by the weighted roller d is employe Thedegree of moisture imparted to the surface of the film a depends on therotating speed of the roller 0 in relation to the speed of travel of thefilm. At the edges, where on account of the direct contact of the filmwith the metal of the roller no even application of the liquid is ableto take place, the liquid spreads by itself from the central portions ofthe film after the latter has left the roller.

In the case of perforated bands of material, such as cinematographicfilm, the arrangement may be such as to provide a supporting ridge orthe like along the margins of the roller on both sides of the filmperforations, thus reventing the film creasing or breaking a ong theseof its weakest portions.

What I claim is 1. A device for applying liquid to cinematographic filmbands comprising in combination, a roller wheel supported for freerotation in a bath of the liquid and having a shallow circumferentialdepression or groove,

of a width slightly less than the width of the bands and deepenedmarginally between lateral ridges of its peripheral surface; guide rollsby which the bands reeled from one point to another are trained over anarc of the wheel with their margins contacting said rid es and theireffective film surfaces bri ging said groove in exposure to the liquidpicked up and carried therein by capillary action with rotation of thewheel; means for reeling the bands from said one point to another; andmeans for regulating the tension of the bands upon said wheel, thelatter being rotated by friction thereon of the moving bands and thequantity of liquid picked up thereby and applied to the bands beingvariable directly with the speed of reeling the same.

' 2. In a device for applying surface treating liquid to one side of afilm ba (1, a roller wheel supported for free rotation in a bath of theliquid and having a circumferential depression or groove of shallowdepth and of width only slightly less than the width of the band inwhich the liquid is picked up and carried by capillary actlon withrotation of the wheel effected by the band passing thereo'ver in reelingfrom one point to another, and guide-rolls training the band upon thewheel in bridgement of its said depression so that the effective filmsurface will be exposed to the liquid therein without contacting thewheel surface, the quantity of liquid picked up by the wheel and soapplied to the band being variable with the speed of the moving band.

3. A device for applying surface treating tion of the wheel; means forreeling the bands liquid to one side of film bands comprising from saidone point to another; and means in combination, a roller wheel supportedfor for tensioning the same on the wheel, the latfree rotation in a bathof the liquid and havter being driven by friction of the moving ing ashallow circumferential depression or bands thereagainst.

groove of a width slightly less than the width of the bands and lateralmarginal ridges; guide-rolls by which the bands reeled from one point toanother are trained over an I are of the wheel with their marginscontacting said ridges and their effective film surfaces bridging saidgrooves in exposure to the liquid picked up and carried therein bycapillary action with rotation ofthe wheel; means for reeling the bandsfrom said one point to another; and means for regulating the tension ofthe bands upon said wheel, said means including a weighted rollersuspended by depending loops of the bands; said wheel being rotated byfriction thereon of the moving bands while the quantity of liquid pickedup thereby and applied to the bands will be variable directly with thespeed of reeling the latter.

4. In a device for applying liquid to film bands according to thepreceding claim, electric contacts arranged above and below the weightedroller and adapted to actuation thereby for closing the indicatorcircuit whenever the tension on the moving band becoming slack orexcessive lowers or raises said roller thereagainst.

5. In a device for applying a treating liquid to one side of a filmband, a roller wheel supported to rotate freely in a bath of the liquidand having a peripheral depression of shallow depth and of a width onlyslightly less than the width of the band over which the latter is passedin reeling from one point to another, said band being trained upon anarc of the wheel with its intermediate. portion bringing said depressionso as to be directly exposed to the liquid lifted up and carried thereinby capillary action upon rotation of the wheel; means for reeling theband from said one point to another and a yieldingtensioning device formaintaining the required tension of the band on said wheel, the latterbeing rotated by friction ofthe band in moving thereagainst.

6. A device for applying a treating fluid to one side of bands or stripsof material comprislng 1n combmation, a roller wheel supported for freerotation in a bath of the quid and having a shallow circumferentialdepression or groove of a width slightly less than the width of thebands and deepened marginally between lateral ridges of its pe ripheralsurface; guide-rolls by which the bands reeled from one point to anotherare trained over an arc of the wheel with their exposure to a film ofliquidpicked up and carried therein by capillary action with rota-

